<div class="row">
  <div class="col-lg-4" *ngFor="let s of sl" >
    <img class="rounded-circle img" src="{{s.img}}" alt="Generic placeholder image" width="140" height="120" />
    <h2>{{s.title}}</h2>
    <p>{{s.summary}}</p>
    <p><a class="btn btn-secondary" href="#" role="button">查看详细 &raquo;</a></p>
  </div>
</div>